Home
HelpTest Code OS Osmolality
Synonyms/Keywords
Osmo
Specimen Requirements
| Fasting Required | Specimen Type | Preferred Container/Tube | Acceptable Container/Tube | Specimen Volume | Specimen Minimum Volume (allows for 1 repeat) |
Pediatric Minimum Volume (no repeat) |
|---|---|---|---|---|---|---|
| No | Serum or Plasma | Red Top Tube (RTT) or Serum Separator Tube (SST) | Lithium-heparin Plasma Separator Tube (PST), Sodium-heparin Green Top Tube (GTT) | 1.0 mL | 0.2 mL | 0.1 mL |
Collection/Processing Instructions
Previously collected specimens are acceptable up to 2 hours on cells.
Indicate collection time.
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Serum/Plasma | Ambient | 3 hours |
| Refrigerated | 5 days | |
| Frozen | 3 months |
Test Information
Calculating osmolality using 2 x Na + BUN/3 + Glucose/20 and subtracting from the measured osmolality gives the osmolal gap. Gaps measured on non-acute outpatients gave values in the range of -5 to +9 using this formula. An elevated osmolality and a gap > 10 suggests the presence of circulating volatiles or other low molecular weight species.
Reference Range Information
| Performing Location | Reference Range |
|---|---|
| All Performing Sites | 282 - 305 mOs/kg |
Marshfield Labs Performing Department
Marshfield Labs Urinalysis
Performing Information
| Performing Location | Day(s) Test Performed | Analytical Time | Methodology/Instrumentation |
|---|---|---|---|
| Beaver Dam | Monday through Sunday | Less than 2 hours | Freezing-Point Depression |
| Weston | Monday through Sunday | Less than 2 hours | Freezing-Point Depression |
| Eau Claire | Monday through Sunday | Less than 2 hours | Freezing-Point Depression |
| Park Falls | Monday through Sunday | Less than 2 hours | Freezing-Point Depression |
| Marshfield | Monday through Sunday | Less than 2 hours | Freezing-Point Depression |
| Neillsville | Monday through Sunday | Less than 2 hours | Freezing-Point Depression |
| Minocqua | Monday through Sunday | Less than 2 hours | Freezing-Point Depression |
CPT Codes
| CPT | Modifier (if needed) |
Quantity | Description | Comments |
|---|---|---|---|---|
| 83930 |
Outreach CPT Codes
| CPT | Modifier (if needed) |
Quantity | Description | Comments |
|---|---|---|---|---|
| 83930 |
Ordering Applications
| Ordering Application | Description |
|---|---|
| Cerner | Osmolality |